If you parse the strings "today", "yesterday", or "tomorrow" in order to get the time now, or 24 hours in the past/future, this will no longer work. These strings now refer strictly to the date (so "today" is the current day at midnight, "yesterday" is the previous day at midnight, etc.).

To get the time now, 24 hours ago, or 24 hours in the future, you would need to parse the strings "now", "-24:00:00", or "+24:00:00" respectively.

In 5.xx, it was documented that you could use the module Memoize to speed up Date::Manip, especially when sorting dates.

This information is no longer accurate. Using Memoize in conjunction with Date::Manip should have little impact on performance, and may lead to incorrect results, especially if you change config variables.